We look at the division of 84457251 by 991 
The aim is to understand the frequency of 991 in 84457251.

Going ahead to step 1:
The number 991 fits into 8 0 times, leaving a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Grab the next digit (4) from the dividend, add it to 8, then carry on: 84 / 991

On to step 2:
The number 991 fits into 84 0 times, leaving a remainder of 84.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 84, we end up with 84.
Bring next digit (4) of the dividend behind the 84 and repeat the process: 844 / 991

Step 3:
When dividing 844 by 991, we get 0 with a remainder of 844.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 844 and we're left with 844.
Include the next digit (5) from the dividend after 844, then repeat: 8445 / 991

Step 4:
8445 divided by 991 is 8 with a remainder of 517.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
If we subtract 7928 from 8445, we get 517.
Append the next digit (7) from the dividend to 517 and continue with: 5177 / 991

Advancing to step 5:
991 can be fit into 5177 5 times, resulting in a remainder of 222.
The number 5 becomes the next digit in our result. 
Result so far: 85.0
Deduct 4955 from 5177 and we're left with 222.
Take the next digit (2) from the dividend and append it to 222, then repeat: 2222 / 991

Advancing to step 6:
991 can be fit into 2222 2 times, resulting in a remainder of 240.
Use 2 as the next digit of our solution. 
Result so far: 852.0
The remainder is 240 after subtracting 1982 from 2222.
Fetch the next digit (5) from the dividend, attach it to 240 and continue: 2405 / 991

Let's proceed to step 7:
2405 divided by 991 is 2 with a remainder of 423.
Use 2 as the next digit of our solution. 
Result so far: 8522.0
If we subtract 1982 from 2405, we get 423.
Fetch the next digit (1) from the dividend, attach it to 423 and continue: 4231 / 991

On to step 8:
When dividing 4231 by 991, we get 4 with a remainder of 267.
Put 4 as the next digit of the answer. 
Result so far: 85224.0
Subtract 3964 from 4231 to get 267.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2670, and continue the process.

Moving on to step 9:
2670 divided by 991 is 2 with a remainder of 688.
Put 2 as the next digit of the answer. 
Result so far: 85224.2
If we take 1982 away from 2670, we end up with 688.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6880, and continue the process.

Step 10:
991 goes into 6880 6 times with a remainder of 934.
The number 6 becomes the next digit in our result. 
Result so far: 85224.26
If we take 5946 away from 6880, we end up with 934.
Since there are no more digits in the dividend, we add a zero to the remainder making it 9340, and continue the process.

Advancing to step 11:
When dividing 9340 by 991, we get 9 with a remainder of 421.
Put 9 as the next digit of the answer. 
Result so far: 85224.269
Deduct 8919 from 9340 and we're left with 421.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4210, and continue the process.

Let's proceed to step 12:
The number 991 fits into 4210 4 times, leaving a remainder of 246.
The number 4 becomes the next digit in our result. 
Result so far: 85224.2694
The remainder is 246 after subtracting 3964 from 4210.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2460, and continue the process.

Advancing to step 13:
991 goes into 2460 2 times with a remainder of 478.
Record the quotient 2 as the next digit in the result. 
Result so far: 85224.26942
If we take 1982 away from 2460, we end up with 478.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4780, and continue the process.

Going ahead to step 14:
4780 divided by 991 is 4 with a remainder of 816.
Put 4 as the next digit of the answer. 
Result so far: 85224.269424
The remainder is 816 after subtracting 3964 from 4780.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8160, and continue the process.

On to step 15:
If we divide 8160 by 991, we get 8 and a remainder of 232.
Write down 8 as next digit of the result. 
Result so far: 85224.2694248
If we subtract 7928 from 8160, we get 232.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2320, and continue the process.

On to step 16:
When dividing 2320 by 991, we get 2 with a remainder of 338.
Record the quotient 2 as the next digit in the result. 
Result so far: 85224.26942482
The remainder is 338 after subtracting 1982 from 2320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3380, and continue the process.

The final result is 85224.26942482 with a remainder of 3.38e-07.